The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Displays that represent the outside world when worn on a user's head may have noticeable latency in keeping up with the user's motion. Also, displays that are worn on the head in an environment with significant noise and vibration can be difficult to view. In particular, high frequency content, such as text may be totally unreadable. This can be a problem with any head wearable device due to the requirement to track the users head position, but particularly so when worn in high noise and vibration environments such as aircraft cockpits. The latency associated with offset measurement and image rendering is simply too high to usefully counteract this issue. Predictive models associated with fixed vibration frequencies can improve the image, but cannot properly account for random noise. Fixing the display relative to the head, using a user specific helmet mounting can also improve the system, but the nature of helmets requires that there be some elasticity between the users head and the helmet so that the helmet can fulfill its primary purpose, protecting the wearer's head. This elasticity also contributes to the noise and vibration and may even introduce additional modes in the vibration that need to be dealt with.